Perhaps you should try some spelling variations:
thanh trung » thanh tung
hieu manh » chieu xanh, hieu nganh, dieu hanh
thien anh » thien danh, tien anh, thien thanh
trong dan » trong dang, trong san, trong tan
trung su » trung vu, trong su, trung du
dan toan » van toan, dan than, manh toan
toan cao » toan ban, toan tap

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((hieu manh) or (thien anh)) - thanh trung su dung trong dan toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hieu manh) OR (thien anh)) - thanh trung su dung trong dan toan cao.
• Adding a wildcard symbol may retrieve word variants: hoc ((hieu manh) or (thien anh)) - thanh trung su dung trong dan toan cao*.